The present invention relates to a curable composition containing a phenol resin and a polyether having a silicon-containing reactive group, which provides a cured product having improved properties in flexibility, impact resistance, toughness and strength.
A phenol resin has hitherto been used for various purposes, for instance, used as molding materials, adhesives and paint or coating materials, or in plywoods and laminates. However, it has the defect that the cured product is brittle, which is a problem common to these uses.
Various polymers having a silicon-containing reactive group are known. For instance, hydrolyzable silyl group-containing polymers are curable to form cured products by exposure to moisture in the atmosphere. A polyether having a silicon-containing reactive group has an interesting property such that it is cured even at ordinary temperature to form a rubber-like elastomer, but has the defect that the strength of the cured product is small and, therefore, is restricted in its uses.
An object of the present invention is to improve the brittleness of the cured phenol resin and the strength of the cured polyether having a silicon-containing reactive group.
A further object of the present invention is to provide a curable composition of a phenol resin which eliminates the defects of the cured phenol resin, namely impact resistance, flexibility, toughness, peeling strength and the like.
A still further object of the present invention is to provide a curable composition of a polyether having a silicon-containing reactive group which eliminates the defects of the cured polyether, namely strength and the like.
These and other objects of the present invention will become apparent from the description hereinafter.